Power pitching bullgrader

ABSTRACT

Power-adjusted bulldozing attachment for a tractor having a Cframe and a bullgrading blade capable of pitching, tilting, and angling. A mid-region of the blade has a universal mounting on the base of the C-frame. Pairs of strut member incorporating power units are connected to the ends of the blade and the legs of the C-frame for pitching and tilting the blade. The blade is angled by shifting the struts along tracks on the legs of the Cframe. The struts are fixed at various locations on the frame by the use of lock pieces on the struts and spaced slots in the tracks receiving the lock pieces.

United States Patent Winkler [54] POWER PITCHING BULLGRADER [72] Inventor: Bernard L. Winkler, Chicago, 111.

[73] Assignee: International Harvester Company,

Chicago, 111.

[22] Filed: Jan. 12, 1970 21 Appl. No.: 2,207

[52] US. Cl ..172/804, 172/805 [51] Int. Cl. ..E02f 3/76 [58] Field of Search ..172/804-809, 803, 172/801 [56] References Cited UNITED STATES PATENTS 3,059,356 10/1962 Lorang ..172/804 3,400,767 9/1968 l-lermiz Harrell 1 72/805 [15] 3,655,000 [4 1 Apr. 11, 1972 3,386,519 6/1968 Long ..172/805 3,521,714 7/1970 Farris ..172/804 Primary Examiner-Robert E. Pulfrey Assistant Examiner-Stephen C. Pellegrino Attorney-Floyd B. Harman [5 7] ABSTRACT Power-adjusted bulldozing attachment for a tractor having a C-frame and a bullgrading blade capable of pitching, tilting, and angling. A mid-region of the blade has a universal mounting on the base of'the C-frame. Pairs of strut member incorporating power units are connected to the ends of the blade and the legs of the C-frame for pitching and tilting the blade. The blade is angled by shifting the struts along tracks on the legs of the C-frame. The struts are fixed at various locations on the frame by the use of lock pieces on the struts and spaced slots in the tracks receiving the lock pieces.

3 Claims, 7 Drawing Figures POWER PIT CHING BULLGRADER The present invention relates to a bulldozing attachment for a tractor. More specifically, the invention provides for various kinds of movement of a bullgrading blade which moves both with and relative to a single supporting C-frame in the attachment.

It is known to give a bulldozing blade movements by mounting structures such as a tilting structure, or a pitching structure, or an angling structure for best use of the blade. The difficulty has been that the mounting structures accommodating such movements have been bulky, heavy, complicated, limited in versatility, and expensive.

An object of the present invention is to provide a simplified mounting for a bulldozing blade that will avoid the aforementioned difficulty, and afford a whole series of movements.

From the later following description of my assembly of a mounting C-frame and a bullgrader blade mounted thereon, it will become apparent that I provide an improved arrangement of such frame and blade assembly, characterized by: the blade having lower struts with ends lockable to the C-frame legs; the blade at the lower end sections having joints connecting same to the lower struts which, when the strut ends are locked to points on the C-frame legs, establish locked positions of the blade; the blade having tilt struts between the lower strut lockable ends and the blade upper end sections; the blade having at its lower center section a joint connecting same to the C-frame and defining a first transverse axis extending upright, second transverse axis extending horizontally fore and aft, and third transverse axis in an athwart position of the C-frame, extending horizontally crosswise; power means associated with the lockable blade to angle same about the first transverse axis between locked positions; oppositely coacting cylinders operatively associated with the second transverse axis and tilt struts to tilt the blade about the second axis between selected tilt angles; the joints at the lower center section and at the lower end sections of the blade characterized by aligned ball joints; and similarly coacting cylinders operatively associated with the third transverse axis and tilt struts to pitch the blade about the third axis between selected suction angles.

A specific object, therefore, is to provide an improved mounting C-frame structure for mounting a blade to impart pitching movement thereto.

A further specific object is to provide an improved structure mounting a blade for giving it angling movement.

Other objects will appear from the detailed description that follows and the attached drawings.

In the drawings:

FIG. 1 is a plan view of the bulldozing attachment of the present invention;

FIG. 2 is a side view of the attachment;

FIG. 3 is a plan view of a track forming an inventive part of the present attachment;

FIG. 4 is a side view of the track;

F IG. 5 is an end view of the track;

FIG. 6 is a vertical sectional view taken on the line 6-6 of FIG. 1 showing the connection of strut means to a track; and

FIG. 7 is a horizontal sectional view taken on the line 7--7 of FIG. 6.

As shown in FIG. 1, a bulldozing attachment 10 comprises a C-frame l1 and a blade 12 adjustably connected thereto. By means of fixed trunnions, not shown, the C-frame 11 in customary way has the free ends of legs 13 pivotally connected on an axis 14 to a tractor 15. A base 16 of the C-frame 11 has its mid-region connected to a lower central section or mid-region of the blade 12 by means of a pin member 17 secured to the base 16 and a socket member 18 secured to the blade 12. The pin member 17 has a spherical ball head 19 which is received in a spherical cavity in the socket member 18 to form a universal mounting joint of the general type hereinafter referred to variously as ball type connection or simply ball joint or ball connection.

As shown in FIGS. 1 and 2, two strut means 20 are .provided, one of which is connected to one end of the blade 12 connected to the other end of the blade 12 and the other leg 13 of the C-frame 11. Each strut means 20 comprises a lower strut 21 of fixed length and an upper strut 22 of adjustable length. One end of the lower strut 21 is connected with a lower region of the end of the blade 12 by a joint of the ball type, and the other end of the lower strut 21 is connected to a trunnion ball 23. At one end of the upper link 22 I use another ball-type connection, made to an upper region of the end of the blade 12, and the opposite end of the link 22 is connected with the lower link 21 near or at the end thereof away from the blade 12. The upper link 22 incorporates a hydraulic power unit 24 composed of a cylinder 25, a piston (not shown) slidably mounted therein, and a piston rod 26 secured to the piston and projecting from the cylinder 25.

As shown in FIGS. 1, 2, 6, and 7, the trunnion ball 23 is secured to the side of a housing 27, which is mounted on and receives a track 28 secured to the top of the leg 13 of the C- frame 11. As shown in FIG. 5, the track 28 is of cross shape and has opposed flanges 29 extending from opposite sides thereof in spaced relation to the top and the bottom of the track 28. As shown in FIGS. 3 and 4, the track 28 has a plurality of slots 30, which may be three in number as shown, located at longitudinally spaced regions of the track and extending from the top thereof with open sides down to the flanges 29. The bottom of each slot 30 is crowned in two sloping surfaces 31 so as to be self-cleaning. The ends of each slot 30 are arcuate so as to accommodate a lock piece 32 of circular shape, which is vertically slidably into and out of the slot 30 in a cir cular cylindrical bore 33 formed in the housing 27.

The lock piece 32 has a vertical bolt hole through which it is loosely attached by means of a bolt 34 to the end of a piston 35 protruding from a cylinder 36. The other end of the piston 35 is enlarged and is slidably mounted in the cylinder 36. The cylinder is attached to the upper portion of the bore 33 in the housing 27. Seals 37 for a chamber 38 formed between the piston 35 and cylinder 36 are located in grooves fonned on the enlarged end of the piston 35 and in a reduced end of the cylinder 36 through which the piston 35 protrudes. A coil spring 39 acting between the end of a deep recess in the upper end of the piston 35 and the inside of a cover 40 attached to the top of the housing 27, yieldingly holds the lock piece 32 in the slot 30. Hydraulic fluid supplied through a passage 41 formed in the housing 27 and cylinder 36 to the chamber 38 will move the piston 35 upwards and thus lift the lock piece 32 out of the slot 30. The housing 27 has a cruciform slot receiving the track 28 and its flanges 29 relatively tightly and can be slid along the track 28 for engagement of the lock piece 32 in any of the three slots 30 shown. Relief passages 41a extending from the bore 33 in the housing 27 to the exterior thereof are provided. Any soil that may adhere to the bore 33 will be extruded out through passages 41a as the lock piece 32 is depressed.

For angling of the track 28 with respect to the C-frame 11 involving angular movement of the blade 12 about a vertical axis through the ball head 19 on the pin member 17, the lock pieces 32 are released from the slots 30 in the tracks 28 by being raised, and the blade 12 is angled as desired, one housing 27 and its lock piece 32 moving forwardly to the front slot 30 on the one track 28, and the other housing 27 and its lock piece 32 moving rearwardly to the rear slot 30 on the other track 28. The blade 12 is angled by means of a hydraulic power unit 42 connected at one end to the blade 12 and at the other end to the base 16 of the C-frame 11. Alternatively, the blade 12 may be angled by application of tractive effort against one end of the blade or by steering of the tractor to the left or right while the blade is under a bulldozing load. Such operations are, of course, carried out while the lock pieces 32 are raised out of the slots 30.

Pitching of the blade 12 with respect to the frame 11, involving angular movement about a horizontal axis transverse of the tractor 15, is accomplished by the same adjustment-of the upper struts 22 of both strut means 20, i.e., either and one leg 13 of the C-frame l1, and the other of which is lengthening or shortening, by actuation of the power units 24.

Tilting of the blade 12 with respect to the frame 11 involving movement about a horizontal axis longitudinal of the tractor is produced by lengthening of the upper strut 22 of one strut means 20 and the shortening of the upper strut 22 of the other strut means 20.

In an alternate construction, the lock pieces 32 can be moved in and out of the sockets 30 in the tracks 28 by manually acutatable rods or the like, instead of the hydraulic pistons 35.

It should be observed that tilting, pitching, and angling of the blade 12 are in a sense centered in the two strut means 20. Angling of the blade takes place by movement of the housings 27 connected to the struts 21 of the strut means 20 along the tracks 28. Pitching of the blade 12 takes place by virtue of adjustment of one sort of the upper links 22 of the link means 20. Tilting occurs because of adjustment of a different sort of the upper links 22. These three movements of the blade 12 with respect to the frame 11 are centered in the two strut means 20, because the swivel connection of the blade 12 with the base 16 of the frame 11 in the socket member 18 and the ball head 19 (FIG. 1) is on a line extending athwart of the C-frame between the ball joint connections of the lower struts 21 with the blade 12.

It is also worthy of note that the tractor operator can tilt, pitch, elevate, and angle the blade to a precise attitude without leaving the seat of the tractor, for the controls for the power units 24 and 42 and the pistons 35 in cylinders 33 producing such movements are within easy reach of the tractor seat. Likewise, a control for hydraulic power cylinders 43 acting between the C-frame l1 and tractor for pivoting the C-frame 11 up and down at the front of the tractor with respect to the axis 14, is also located convenient to the operators seat. The usual cylinder circuits include pumps, reservoir, control valves, hoses, and conduits in customary way and, for simplification, are not illustrated.

It will now be appreciated, in the present angling attachment for a tractor to do bullgrading work, that I provide improvements in operation, and improvements in structure, namely, a novel arrangement of an angling adjustment means comprising: a slidably related rail and housing; the rail having transverse lock receiving slots therein; a lock in the housing having shifting means for retracting and advancing same away from the rail and theretoward so as to be received in a selected receiving slot; said lock when in a slot effectively keying together the slidably related housing and rail, and having a transversely defiectible connection to the shifting means whereby the lock is placed in shear over a large area when keyed in the slot without creating bending or shearing stresses in the shifting means; the retractively and advancingly shifting connection characterized by a pin 34 connected to the shifting means; and an opening in the lock in which the pin fits so as to be loose in all diametric directions as viewed in cross section.

In other words, only the lock pieces 32 are subject to the loads imposed on the blade 12, which are transmitted through the strut means 20, the trunnion balls 23, and the housings 27 to the lock pieces 32. Such loads on the lock pieces 32 will not be transmitted to the pistons 35 and the seals 37, because the bolts 34 have side play in the bolt holes in the lock pieces 32 and thus loosely attach the lock pieces to the pistons. Thus, the pistons and the seals 37 have a long service life. Since the lock pieces are merely bolted to the pistons, the lock pieces can easily be replaced as wear occurs.

What is claimed is:

l. A bulldozer attachment for a tractor, comprising a C- frame having two spaced legs and a base connecting the legs, the ends of the legs remote from the base being adapted to be pivotally connected to opposite sides of the tractor, a blade extending along the base of the C-frame, means pivotally connecting a mid-region of the blade with a mid-region of the base of the C-frame, two pairs of struts for pitching and tilting the blade, one strut of each pair being of adjustable length and the other strut of fixed length, the struts of one pair being connected to vertically spaced regions of the blade near one end thereof, the struts of the other pair being connected to vertically spaced regions of the blade near the other end thereof, the struts of one pair being connected to one another at their ends remote from the blade, the struts of the other pair being connected to one another at their ends remote from the blade, a pair of tracks, one being secured to and extending along one leg of the C-frame, the other being secured to and extending along the other leg of the C-frame, each track having a pair of flanges extending from opposite sides in spaced relation to the associated leg of the C-frame so as to give the trackia cross shape, each track having a plurality of slots spaced from one another along the track and located in the portion beyond the flanges and on the side thereof away from the associated leg of the C-frame, the slots being open at their sides and having crowned ends each at a point between the flanges, a pair of housings, each having a cruciform slot, one housing receiving one rail in its cruciform slot so as to be slidable along said one rail to and between the slots therein, the other housing being similarly associated with the other rail, a pair of lockpieces, one lockpiece being slidably mounted for operative movement in said one housing so as to be engageable with the slots in the said one track, and having means for so moving same, the other lockpiece being similarly operatively moved and associated with said other housing and said other track, means pivotally connecting said one housing with said one pair of struts adjacent their connection with one another, and means pivotally connecting said other housing with said other pair of struts adjacent their connection with one another.

2. The bulldozer attachment specified in claim 1 and further comprising a pair of hydraulic power units, each comprising a cylinder and a piston slidably mounted therein, the cylinder of one power unit being secured in the said one housing, the piston of said one power unit being loosely attached to said one lock piece, the cylinder and the piston, respectively, of the other power unit being similarly associated with the said other housing and the said lock piece.

3. In an angling attachment for a tractor to do bullgrading work and including an implement which is angled, the combination comprising:

angling adjustment means comprising a slidably related rail and housing carried at the side of the tractor;

said rail having transverse lock receiving slots therein;

means between the housing and the implement for connecting the former to the latter so as to move with the implement being angled; and

a lock in said housing having shifting means for retracting and advancing said lock away from the rail and theretoward so as to be received in a selected receiving slot;

said lock when in a slot being subjected to locking stresses while effectively keying together the slidably related housing and rail, and having a transversely deflectible connection to the shifting means to avoid stress-transmission, said connection comprising a pin connected to one of the shifting means and lock, and means forming an opening in the other one of the shifting means and lock in which the pin fits so as to be loose in at least one of the diametric directions as viewed in cross section. 

1. A bulldozer attachment for a tractor, comprising a C-frame having two spaced legs and a base connecting the legs, the ends of the legs remote from the base being adapted to be pivotally connected to opposite sides of the tractor, a blade extending along the base of the C-frame, means pivotally connecting a midregion of the blade with a mid-region of the base of the C-frame, two pairs of struts for pitching and tilting the blade, one strut of each pair being of adjustable length and the other strut of fixed length, the struts of one pair being connected to vertically spaced regions of the blade near one end thereof, the struts of the other pair being connected to vertically spaced regions of the blade near the other end thereof, the struts of one pair being connected to one another at their ends remote from the blade, the struts of the other pair being connected to one another at their ends remote from the blade, a pair of tracks, one being secured to and extending along one leg of the C-frame, the other being secured to and extending along the other leg of the C-frame, each track having a pair of flanges extending from opposite sides in spaced relation to the associated leg of the Cframe so as to give the track a cross shape, each track having a plurality of slots spaced from one another along the track and located in the portion beyond the flanges and on the side thereof away from the associated leg of the C-frame, the slots being open at their sides and having crowned ends each at a point between the flanges, a pair of housings, each having a cruciform slot, one housing receiving one rail in its cruciform slot so as to be slidable along said one rail to and between the slots therein, the other housing being similarly associated with the other rail, a pair of lockpieces, one lockpiece being slidably mounted for operative movement in said one housing so as to be engageable with the slots in the said one track, and having means for so moving same, the other lockpiece being similarly operatively moved and associated with said other housing and said other track, means pivotally connecting said one housing with said one pair of struts adjacent their connection with one another, and means pivotally connecting said other housing with said other pair of struts adjacent their connection with one another.
 2. The bulldozer attachment specified in claim 1 and further comprising a pair of hydraulic power units, each comprising a cylinder and a piston slidably mounted therein, the cylinder of one power unit being secured in the said one housing, the piston of said one power unit being loosely attached to said one lock piece, the cyliNder and the piston, respectively, of the other power unit being similarly associated with the said other housing and the said lock piece.
 3. In an angling attachment for a tractor to do bullgrading work and including an implement which is angled, the combination comprising: angling adjustment means comprising a slidably related rail and housing carried at the side of the tractor; said rail having transverse lock receiving slots therein; means between the housing and the implement for connecting the former to the latter so as to move with the implement being angled; and a lock in said housing having shifting means for retracting and advancing said lock away from the rail and theretoward so as to be received in a selected receiving slot; said lock when in a slot being subjected to locking stresses while effectively keying together the slidably related housing and rail, and having a transversely deflectible connection to the shifting means to avoid stress-transmission, said connection comprising a pin connected to one of the shifting means and lock, and means forming an opening in the other one of the shifting means and lock in which the pin fits so as to be loose in at least one of the diametric directions as viewed in cross section. 